Miners continued to rise on Monday – after rebounding at the end of last week – helping to lift the FTSE 100 0.6% to 5745 points at lunchtime.

Investors were reacting to data out of China, released on Saturday and Monday showing the country's vast manufacturing sector has been badly hit by slowing new orders, suggesting the economic slowdown could continue into a seventh quarter.

On Monday, the HSBC China manufacturing purchasing manufacturing index dropped from 49.3 in July to 47.6 in August, the lowest in more than three years. It gives an even grimmer outlook than the official Chinese PMI released on Saturday, which came in at 49.2.

The hope is that Beijing will now act to stem the slowdown in the world's second-largest economy and the world's largest consumer of raw materials. Bhaven Patel of Accendo Markets said Beijing officials may want to gauge the impact of measures taken in June – comprising an interest rate cut and reductions in bank reserve requirements – before they act. But, he writes:

With inflation at a 30-month low of 1.8%, there does remain further scope for the PBOC to act more aggressively. A repeat of the post-2008 ¥4trn stimulus plan may not be on the cards, but does offer evidence that the Chinese can walk the walk. The market view does seem that for today at least the markets are betting that China could be increasingly close to act.

Fresnillo topped the leaderboard, up by almost 4% at £16.23; Kazakhmys was 2.8% higher at 610p; while Vedanta Resources was 2.7% higher at 890.5p.